Open-fire kiln



' Dec. 6, 1927.

r v 1,651,380 P. D'H. DRESSLER OPEN FIRE KILN Filed Aug. 26 1924 gag ATTORNEY Patented Dec. 6, 1927.

UNITED STATES PATENT OFFICE.

YHILIP DHUC DRESSLER, F CLEVELAND, OHIO ASSIGNOR TO AMERICAN DRESSLER TUITNEL KILNS, INC., 03: CLEVELAND, OHIO, A CORPORATION OF NEW YORK.

OPEN-FIRE KILN.

. Application filed. August26, 1924. Serial No. 734,167.

My present invention relates to acontinuous tunnel kiln heated by means of combustion chambers or fire boxes disposed at intervals along the length of the kiln at the 5 sides of the latter and discharging hot products of combustion directly into the kiln chamber; and the general object of the invention is to provide such a kiln with improved means for distributing the heat to H) the goods moving through the kiln,-and in particular to avoid the intense local overheating of the goods in front of the fire boxes which is characteristicof kilns of the type referred to and is objectionable in the case of many kinds of wares treated in such kilns.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification; but for a better understanding of the invention, its advantages and specific objects attained with its use, reference should be had to the accompanying drawings and descriptive matter -in which I have illustrated and described apreferred embodiment of my invention.

Of the drawings: a V Fig. 1 is a diagrammatic plan view of a section; v

Fig. 2 is a partial section on the line 22 of Fig. 1;

Fig. 3 is a partial section on the line 33 of Flg. 2,- and Fig. 4 is a partial section on the line 4-4 of'Fig. 2.

The kiln A shown in the drawings com-. rises a preheating zone A, a furnace or firing zone A and a cooling zone A Distributed along the two sides of the firing zone portion of the kiln are combustion chambers E. The latter may be of any usual or suitable form and, as shown, are provided with grates-E for the combustion of solid fuel but may equally well be heated by the combustion of 011 or gas. Each combustion chamber or fiIQ-fbDX E discharges hot products and burning gasesinto the kiln chamber through a corresponding throat or hot gas outlet E. In'so far as above described I the 'kiln is of a well known type. j

' In accordance with'the present invention the hotgases issuing from each combustion chamberE'through he discharge outlet or tunnel kiln with parts broken away and init is desirable to admit the greater of the heating gases tothe kiln .cham er adthroat E of the latter do not pass directly into the kiln chamber but into anarrow chamber D at the side of the kiln chamber. As shown, there is a chamber D in front of each fire box. The chambers D at each side of the kiln are located between the side wall of the kiln structure proper and a vertical bafile'wall C extending along the lengthof the firing zone and are separated from one another by narrow. artitions d. Advantageously also the wa s C are provided with vertical thickened wedge-like imperforate portions C at their outer sides,one directly in front of 'each combustion chamber throat E. These wedge-like portions C deflect the heating gases from each combustionchamber into the portions of the corresponding chamber D at each side of the axis of the latter, and by reason of their thickness reduce the heat radiation from the correspending portions of the wall C, which otherwise might be excessive. The upper edges of the chamber D advantageously terminatesome distance below the roof arch a of the kiln structure proper and are closed by suitably shaped tiles F. To prevent undesirable longitudinal fiow of the kiln atmosphere through the space between the tiles F and the roof arch suitably located transverse bafiles G .are provided. The heating gases supplied to the chamber D a're'discharged from the latter into the kiln chamber through suitably disposed ports C formed in the walls C. These heating gases after imparting their heat to the wares K, moved through the kiln on the usual kiln cars I, are withdrawn from the kiln adjacent .its exit end as by means of outlets A communicating with a conduit H running to a draft creating device shown as a stack H. With the described construction, the ported walls C prevent the direct radiation of heat from the intensely hot combustion chambers against the wares K, and formmeans for properly distributing the supply of heat along the entire length of the firing zone A of the kiln. The'construction ebviously permits whatever arrangement of i the ports 0 is adapted to secure the desired distribution of heating gases. In general,

ortion jacent the bottom of the space traversed by bottom of the goods pathway, as shown in Fig. 4, than at higher levels. The lowermost ports C may well be located so that the gases discharged by them are directed into the distributing channels I ordinarily formed in the refractory to portions of kiln cars I immediately below t e work supporting surface of the latter. The uniformity of heat distribution obtainable with the invention obviously permits of a rate of heat supply to the kiln which is practically a maximum in the case of wares subject to injury by local overheating. In consequence, the use of the invention tends to increase kiln capacity as well as-to an improved roduct, in firing wares subject to injury y local overheating.

WVhile in accordance with the provisions of the statutes I have illustrated and described the best form of my invention now known to me, it will be apparent to those a skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention as set forth in the appended claims, and that certain features of my invention may sometimes be used to advantage without a corresponding use of other features.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1. In an open fired tunnel kiln provided with fire boxes distributed along the length of the firing zone portion of the kiln at each side of the latter, the improvement which consists in walls between the goods pathway through the kiln and the kiln side walls and uniting with the latter to form chambers receiving the heatin gases from the fire boxes, the first mentioned walls being formed with perforations in their lower portions distributed along a substantial portion of the length of the kiln throughv which the major portion of the heating gases pass into the lower portion of. said pathway.

2. In an open fired tunnel kiln provided with fire boxes distributed alon the length of the firing zone portion of tie kiln, the

improvement which consists in perforated walls between the goods pathway through the kiln and the kiln side walls and unitin with the latter to form chambers re- CGI n the heating gases from the fire boxes and .listributing them thong the length of the kiln, said walls comprisin imperforate portions one in front of each re box.

3. In an open fired tunnel kiln provided with fire boxesdistributed along the length of the firing zone portion of the kiln, the improvement which consists in perforated walls between the goods pathwa through the kiln and the kiln side walls an unitin with the latter to form chambers receiving t e heating gases from the fire boxes and distributing them along the length of the kiln, said walls comprising imperforate portions one in front of each fire box wed e shaped in horizontal cross section to deflect the heating gases from the fire box longitudinally of the kiln in opposite directions.

4. In an open fired tunnel kiln provided with fire boxes distributed along the length of the firing zone portion of the kiln, the improvement which consists in perforated walls between the goods athway through the the kiln and the kiln si e walls and uniting with the latter to form chambers one in front of and receiving the heating gases from each fire box and distributing said gases along the length of the kiln, and V91",

tically extending brick work partitions one between each two adjacent chambers.

5. In an open fired tunnel kiln provided withfire boxes distributed along the length of the firing zone portion of the kiln, the improvement which consists in erforated walls between the goods pathway t rough the kiln and the kiln side walls and uniting with the latter to form chambers receivin heating gases from the fire boxes an disthe tributing them along the len h of the firing zone of the kiln, and bric work spaced away from the kiln roof and closing the upper ends of said chambers. V

6. In an open fired tunnel kiln provided with fire boxes distributed alon the length of the firing zone portion of the kiln, the improvement which consists in perforated walls between the oods pathway through the kiln and the kin side walls and uniting with the latter to form chambers receivin the heating gases from the fire boxes and distributing them alon the length of the firing zone of the kiln, brick work spaced away from the kiln roof and closing the upper endsof said chambers, and transverse bafiles between said brickwork and kiln ['00 w t r at Clevelafid, 0., in the county of Cuyaho'ga and State of Ohio, this 23rd day of August, A. D. 1924. v

v PHILIP DHUC DRESSLER. 

